<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="liYunLong">你真是个天才！</div>
</body>
</html>
<script src="../lib/jquery.js"></script>
<script>
   var tools = {
        fn:function(){
            $('#liYunLong').css('background', 'red')
            return tools
        },
        fn1:function(){
            $('#liYunLong').addClass( 'add')
            return tools
        },
        fn2:function(){
            $('#liYunLong').click(function(){
                alert("总能带来点惊喜")
        })
    }
   }
    tools.fn().fn1().fn2()
</script>

<style>
.add{
    font-size: 30px;
    }
</style>